Fuel supply system



May 26, 1959 I Filed Feb. 27, 1957 ENG/NE TEMPERA TURE c 0 MPE'NSA TOR ELECTRON/C CONTROL A. WINKLER 2,888,000

FUEL- SUPPLY SYSTEM 3 Sheets-Sheet 1 INVENTOR.

MIN-Winkle! ATTORNEY y- 6, 1959 A. H. WINKLER 2,888,000

FUEL SUPPLY SYSTEM Filed Feb. 27, 1957 8 Sheets-Sheet 2 INVENTOR.

We/ZW win/dew A TTOBNE Y 3 Sheets-Sheet 3 AH. WINKLER FUEL SUPPLY SYSTEM WW Elisa INVENTOR.

. 0 w E y fl ///////V ////4! I WW W 5 w I 1 ya a a 0 m T 0 ,//o z Z H .9 9 4 M m v 4 IIIIEIKK May 26, 1959 Filed Feb. 27, 1957 FUEL SUPPLY SYSTEM Albert H. Wiukler, Elmira, N.Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application February 27, 1957, Serial No. 642,903

3 Claims. (Cl. 123-119) The present invention relates generally to fuel supply systems for internal combustion engines and more particularly to a pressure regulator for such systems.

In U.S. Serial No. 567,688 field February 24, 1956, Robert W. Sutton et al., assigned to the assignee of the present invention there is shown a common rail fuel supply system wherein the quantity of fuel supplied to the engine is varied by varying the opening time of the injector nozzle. In the Sutton et al. device altitude compensation is provided by means effective to vary the opening time of the injector nozzles as a function of change in atmospheric pressure.

The present invention has for an object to provide means for varying the pressure of the fuel supplied to an injector nozzles as a function of change in atmospheric pressure.

Other objects and advantages will be readily apparent from the following detailed description taken in connection with the appended drawings in which:

Figure 1 is a schematic view of a fuel supply system embodying my invention;

7 Figure 2 is a sectional view of the pressure regulator shown in Figure 1;

Figure 3 is a front view partly in section of the throttle body shown in Figure 1;

Figure 4 is a sectional view taken along line 4-4 of Figure 1; and

Figure 5 is a sectional view taken along line 5-5 of Figure 1.

United States Patent 0 2,888,000 Patented May 26, 1959 through the induction passage 20. The throttle valves 42 are actuated by a conventional accelerator pedal 46 through appropriate linkage 48. The throttle body 40 carries an acceleration control 50 of the type disclosed and claimed in copending application U.S. Serial No. 622,618 field November 16, 195 6, in the names of Stephen G. Woodward and Curtis A. Hartman and assigned to the assignee of the present application. A thermostatic control 52 is provided for warm-up enrichment.

Referring now to the sectional view of pressure regulator 16 shown in Figure 2, numeral 54 designates a housi ing which is divided into chambers 56 and 58 by a dia- Referring now to the drawings and more particularly to Figure 1, numeral 10 designates a source of fuel, 12 a delivery conduit with a supply pump 14 and a pressure regulator 16 therein. An injector nozzle 18 is connected to delivery conduit 12 and is arranged to inject fuel into the induction passage 20 of an internal combustion engine 22. Delivery conduit 12 is conected back to the source of fuel by means of return conduit 24 which is provided with a restriction 26.

The number of injector nozzles 18 conveniently corresponds with the number of combustion chambers 28 of the engine although the proportion of injectors to combustion chambers may be increased or decreased as desired.

The injectors 18 are arranged to be actuated by an electronic control 30 which is triggered by and connected to the appropriate injector by trigger-distributor unit 32. Unit 32 triggers or energizes the electronic control 30 which remains energized for a controlled time duration. The output of the control 30 is connected to the appropriate injector 18 through unit 32 whereby the injector discharges fuel for the time duration that the electronic control remains energized. The time that the electronic control 30 remains energized is regulated by various sensory elements including engine temperature compensator 34, induction passage pressure responsive element 36 and element 38 responsive to throttle movement.

Throttle body 40 is provided with a pair of throttle valves 42 mounted on a shaft 44 to control the air flow phragm or movable wall 60. Chamber 58 is formed to receive fuel from the delivery conduit 12 through a port 61 and to discharge fuel into conduit 12 through an orifice 62 controlled by a valve 64 which is operatively connected to diaphragm 60 by a rod 66. Diaphragm 60 is provided with a centrally clamped stiffening member 68 which acts as a retainer for the resilient member or spring 70 which is disposed to react between retainer68 and an abutment 72.

Chamber 56 is exposed to the atmosphere through a port 74 formed in housing 54. A bellows or member responsive to atmospheric pressure 76 is mounted in charn ber 56 on an adjustable member 78 which is threadedly received in the housing wall 54. One end of bellows 76 is pivotally connected to one end of a lever 79 which at its other end is pivotally connected to abutment 72. Lever 79 is pivoted or fulcrumed on a stud 80 formed integrally with the housing 54.

As shown in Figure 3, the wiper arm of potentiometer 36 is connected by means of shaft 92 and limbs 94 and 96 to a piston or movable wall 98 mounted in a cylinder 100. A passage 102 connects cylinder to the induction passage 20 downstream or posterior to throttle valves 42. Piston 98 is responsive to induction passage pressure to move the wiper arm 90 toward one of its extreme positions. A spring 104 mounted in cylinder 100 urges piston 98 and wiper arm 90 toward the other of its extreme positions.

As best shown in Figure 4, the wiper arm 106 of potentiometer 38 is connected to the throttle shaft 44 whereby the resistance of potentiometer 38 is a function of throttle position.

The thermostatic control 52 is shown in section in Figure 5 and comprises a housing 108, formed with a cylinder 110 having a connection 112 with the induction passage downstream of the throttle. A piston 114 is reciprocably mounted in cylinder 110 and is connected to a shaft 116 by a rod 118, pivot pin 120 and arm 122. A thermostat 124 is mounted in housing 108 with one end fixed to a stub shaft formed in the housing. The other end of the thermostat is hooked about the pivot pin 120. The thermostatic control 52 functions to set a fast idle cam 126 to obstruct the closing of the throttle valves under certain conditions in a manner well known in the art.

In operation, fuel from source 10 is placed under pressure in delivery conduit 12 by pump 14 from whence it is directed to chamber 58 of the regilator 16. Spring 70 acts on movable wall 60 to urge valve 64 toward open position. Fuel under pressure in chamber 58 acts on wall 60 to oppose spring 70 and to urge the valve 64 toward closed position. The spring 70 is calibrated to maintain the pressure of fuel in conduit 12 at a substantially constant predetermined value.

The pressure in conduit 12 is varied from this predetermined substantially constant value through the action of atmospheric pressure responsive element 76 acting through lever 79 to change the position of abutment 72 and thereby vary the effectiveness of spring 70. Upon an increase in atmospheric pressure bellows 76 will contract urging abutment 72 downwardly to increase the effectiveness of spring 70 and thereby increase the pressure of the fuel in conduit 12. Conversely upon a decrease in atmospheric pressure bellows 76 will expand urging abutment 72 upwardly thereby decreasing the effectiveness of spring 7 and reducing the pressure of the fuel in conduit 12. Increasing the fuel pressure in conduit 12 for a given time duration of injector nozzle opening has the effect of increasing the amount of fuel supplied to the engine. Conversely decreasing the pressure of the fuel in conduit 12 has the effect of decreasing the amount of fuel supplied to the engine for a given time duration of injector nozzle opening.

While only one preferred embodiment of my invention has been described it will be readily apparent to those skilled in the art that many changes of arrangements of parts may be made without departing from the spirit of my invention.

I claim:

1. In a fuel supply system for an internal combustion engine having a source of fuel; a nozzle adapted to discharge fuel to said engine, a conduit connecting said source with said nozzle, a conduit connecting said nozzle back to said source, a valve in said nozzle, means responsive to an engine operating condition for opening said valve for a controlled time duration per power cycle of the engine, means in one of said conduits for maintaining the fuel pressure therein at a predetermined value, and atmospheric pressure responsive means operatively connected to said last mentioned means for modulating said fuel pressure.

2. In a fuel supply system for a multi-cylinder internal combustion engine having a source of fuel; a nozzle for each of said cylinders, a delivery conduit connecting said nozzles to said source, a return conduit connecting said nozzles back to said source, a pump for pressurizing fluid in said delivery conduit, a valve in each of said nozzles, means for periodically opening said valves for a time duration controlled as a function of an engine operating condition, a valve in one of said conduits, resilient means urging said last mentioned valve toward open position, means responsive to the pressure of the fluid in said conduit urging said last mentioned valve toward closed position and means responsive to atmospheric pressure operatively connected to said last mentioned valve to affect the position thereof.

3. In a fuel supply system for an internal combustion engine having a source of fuel; a nozzle adapted to discharge fuel to said engine, a conduit adapted to connect said source with said nozzle, a conduit connecting said nozzle back to said source, a valve in said nozzle, means responsive to an engine operating condition for opening said valve for a controlled time duration per power cycle of the engine, means including a valve in one of said conduits for maintaining the fuel pressure therein at a predetermined value, and a bellows responsive to atmospheric pressure operatively connected to said last mentioned valve for varying said fuel pressure from said predetermined value in response to changes in atmospheric pressure.

References Qited in the file of this patent UNITED STATES PATENTS 2,341,257 Wunsch Feb. 8, 1944 2,408,836 Warner Oct. 8, 1946 

